UVs, smoothing groups and normal map baking
UVs should be pretty basic. Use the techniques you want. If you don't mind about symmetry you can even overlay your symmetrical chunks one above the other, but make sure you know how to mirror a normal map. See Eric Chadwick's page for more information click here.
I strongly recommend reading Chadwick's tutorial as it covers a lot of interesting aspects of normal maps. In there you can not only learn how to mirror a normal map but also how to get incredible results with any complex geometry and any narrow angles and much more. How well the normal map is going to show often depends on the distribution of the smoothing groups on the lowpoly mesh. The "Shaders and Seams" section of the tutorial was the most useful for me while modeling the lowres version of this character.
For my part, the UVs were not mirrored. It gave me more asymmetrical textures but lowered the resolution of the maps because I had to fit more chunks of UV unwrap into one map.
Once the retopo, the UVs and the smoothing groups were done, I brought each separated pieces into Xnormal under "low definition meshes" and brought the highres armor and the ZBrushed anatomy in "high definition meshes" and baked each pieces one by one. This gave me many normal maps, but you can merge them in Photoshop. I had to play with the ray distance in Xnormal until I'd removed every undesired projection since this often happens, especially in narrow places like between the fingers. I had to go back to 3ds Max and play with the smoothing groups a bit more until I got a clean normal map because sometimes angles of less than 90 degrees give weird results and therefore you'll need to add hard edges in the smoothing groups and create UV seams right on these hard edges.
With Xnormal, I also baked the Ambiance Occlusion map too since this really helps to create depth when combined with the normal map.
Textures & Materials
The character was rendered with mental ray only to be able to use the SSS shader to make better beauty shots of the model. The eyes were done with Arch and Design (there are many good tutorials for making eyes on the net) and the armor was done using a standard 3ds Max material with "Strauss" selected in the Shader Basic Parameters. The Strauss shading gives unsatisfying results at first but it can be tweaked to give a nice metal effect! Now the reason why I didn't use Arch and Design for the armor is simply because Arch and Design (not every mental ray shader) seems to have a problem with the smoothing groups when a normal map is applied above it. Probably some kind of tangent space incompatibility in 3ds Max. Since shaders are not really my specialty, I won't go in more details (Fig.07).
There is nothing really special about the maps. There are two different groups of maps: the maps for the armor, and the ones for the anatomy. For the armor, I got a normal map, a specular map, a diffuse map (Fig.08) and an extra opacity for the visor part. For the anatomy, I got a spec, a normal map, a grayscale map to control the weight of the SSS skin effect and the specular narrowness on the bikini part (Fig.09) and three maps for the SS skin shader: unscattered, epidermal, sub-scattered (Fig.10).
Note: I often use the same maps for different purposes: in 3ds Max: I just play with the output of the map in the material editor to change the map's grayscale value or color. That way I don't have to go in and out of Photoshop to make changes on my maps and I can use the same texture file for different purposes with my shaders.
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